lp5526tlx National Semiconductor Corporation, lp5526tlx Datasheet - Page 9

• Manufacturer Part Number: lp5526tlx
• Description: Lighting Management Unit With High Voltage Boost Converter With Up To 150ma Serial Flash Led Driver
• Manufacturer: National Semiconductor Corporation

I
I
V
RDS
f
t
t
I
Symbol
LOAD
LOAD
PWM
PULSE
STARTUP
MAX
OUT
Magnetic Boost DC/DC Converter
MAGNETIC BOOST DC/DC CONVERTER ELECTRICAL CHARACTERISTICS
Note: Maximum non-continuous currents rates as short pulses (t
BOOST STANDBY MODE
User can set the Boost Converter to STANDBY mode by
writing the register bit EN_BOOST low. When EN_BOOST is
written high, the converter starts for 20ms in low current
PWM mode and then goes to normal PWM mode. All LED
outputs are off during the 20ms delay to ensure smooth
startup.
BOOST OUTPUT VOLTAGE CONTROL
User can control the boost output voltage by Boost Output
8-bit register.
If register value is lower than 8, then value of 8 is used
internally.
If register value is higher than 20, then value of 20 is used
internally.
ON
0000 1000
0000 1001
0000 1010
0001 0000
0001 0001
0001 0010
0001 0100
0000 1011
0000 1100
0000 1101
0001 0011
0000 1110
0000 1111
Bin
Maximum Non-Continuous
Load Current
Maximum Continuous Load
Current
Output Voltage Accuracy
(FB Pin)
Switch ON Resistance
PWM Mode Switching
Frequency
Frequency Accuracy
Switch Pulse Minimum
Width
Startup Time
SW Pin Current Limit
Boost Output [7:0]
Register 0DH
Parameter
Dec
10
12
13
14
15
16
17
18
19
20
11
8
9
Voltage (typical)
3.0V ≤ V
V
3.2V
V
3.0V = V
V
3.0V ≤ V
V
I
RT = 82 kΩ
RT = 82 kΩ
no load
Boost startup from STANDBY to V
= 20V, no load
Boost Output
SW
OUT
OUT
OUT
OUT
= 0.5A
10.0V
12.0V
13.0V
14.0V
15.0V
16.0V
17.0V
18.0V
19.0V
20.0V
11.0V
8.0V
9.0V
<
= 20V
= 20V
= 20V
= 20V
V
IN
IN
IN
IN
<
≤ 3.2V
≤ 5.5V
1s). Exposure to maximum rating conditions for extended periods may affect device reliability.
Conditions
(Continued)
9
OUT
Boost Output Voltage Control
−2.3
Min
-1.7
−7
−9
1500
0.15
Typ
1.0
45
15
1850
Max
+2.3
+1.7
140
150
100
0.3
20179778
+7
+9
www.national.com
Units
MHz
mA
mA
ms
ns
%
%
Ω